Columbia announced its new double-sided discs in a two-page ad in The Talking Machine World, September 15, 1908, pages 34-35. The ad shows Columbia A5053 (12").
An article two pages later reports that ca."600 numbers" are being released, page 37: “ Columbia Co. Spring Double Disc Sensation”.
The first new records listed after that, in the October 15, 1908 issue on page 54 (for Nov., 1908), are Columbia A409; A590-A599.
So we can safely assume that all other A-prefix releases up to A589 were released on September 20, 1908 (the 20th of the month was Columbia's official release date).
As many obviously mistook the new release date notation on DAHR, that site has returned to the generally intelligible notation, e.g. "Release Date: 1908" for this one here (A392), instead of "1/1/1908", and "Release Date: 12/1908" for Columbia A616 linked below, no more "12/1/1908".
Consequently I have corrected several misunderstood "first day of the month/year" release dates here.
As already requested by a user in the corrections, please always check and scrutinize the release dates on DAHR, especially now as they have changed the way of presentation considerably. For example, all double sided Columbia records from A1 to A589, listed as released in 1908 before, are now listed there as released on "1/1/1908" what apparently still means just 1908, not January 1, 1908.
The first Columbia release dates I can verify are for A613 to A616 which were announced in Talking Machine World of December 1908 (p. 53) "for January, 1909". DAHR lists these four records with issue date "12/1/1908", apparently meaning December 1908 what seems reasonable and was considered here for A616 some time ago.
So 1908 seems better than an exact date for this one here anyway, although an earlier release year cannot be ruled out (both sides were recorded earlier and had been released on one-sided records before).